Great Plains NH3 Safety User Manual
Page 17
Great Plains Manufacturing, Inc.
Ammonia Nurse Tanks
13
2013-07-15
407-551M
Refer to Figure 7
A61 Hose Valve(s)
If the nurse tank hose has one or more valves, study
how they work.
Refer to Figure 8
A62 Bleed Valve(s):
Hose valves typically have bleed valves. The
purpose of a bleed valve is to perform a controlled
release, via an orifice
, of any fluid or gas
trapped in the closed line prior to disconnect at a
nearby Acme fitting.
A single bleed valve may be located on the inlet or
outlet side of the valve, and only protects that side
of the circuit when the valve is closed. More rarely, a
shut-off valve has bleed valves on both sides of the
valve.
Study the location of all bleed valves on your nurse
tank and implement.
Hose valves are typically hand wheel valves (as
shown
), or lever valves. Read any documents
provided for the valves. Have the terminal or dealer
explain how the valves work.
Suffocation, Blinding and Burning Hazards:
Never test an anhydrous ammonia hose valve unless you
are absolutely certain the hose and valve bodies are
empty, or both hose ends are securely connected to sealed
systems.
▲ A two-valve hose can contain a substantial amount of
NH
3
even when completely disconnected. See “Avoid
▲ Older ball valves can contain NH
3
inside the ball when
closed, even though disconnected at both ends.
See “Avoid Ball Traps” on page 38.
Follow instructions for bleeding and checking. Never use
a valve handle as a carrying handle. Keep hands clear of
bleed valves when carrying a hose.
Suffocation, Blinding and Burning Hazards:
Be up-wind when operating a bleed valve.
Wear chemical gloves when operating a bleed valve.
Wear goggles when operating a bleed valve.
Do not place your body or head in front of the orifice.
Follow a check-list when operating a bleed valve.
Open a bleed valve slowly.
A61b
A62
Figure 7
Hose Shut-Off and Bleed Valves
31535
A61b
Figure 8
Bleed Valve
Detail
31569
A62a
A62a